1. Field of the Invention
The present invention relates to surface hardened aluminum parts in which a hardened layer possessing high resistance to abrasion and heat is formed on the surface of an aluminum base material made of aluminum or an aluminum alloy, and to a method of producing same.
2. Description of the Prior Art
Thanks to its small specific gravity (=2.7) and excellent corrosion resistance, aluminum has come into wide use for a variety of mechanical parts, e.g. in industrial robots, automobiles, and aircraft. However aluminum materials have markedly inferior abrasion resistance and heat resistance, compared with iron materials, and this could be a serious bar to employing aluminum parts in place of iron parts for the purpose of seeking light weight.
up to now, there have been proposed various techniques of forming a hardened layer (i.e., a hardened alloy layer), on the surface of an aluminum part to be provided in a position where high abrasion resistance and high heat resistance are required. One of those techniques that have been put to practical use is the so-called laser alloying method in which a powder of metal such as iron Fe, nickel Ni and cobalt Co is supplied onto an aluminum base material made of aluminum or an aluminum alloy and this powder metal is melted using a high-density energy heat source such as laser beams so as to be alloyed with the aluminum or aluminum alloy contained in the aluminum base material.